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How much crosstalk (ghosting) has your 3D TV? Test it!

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Old 10-08-2012, 9:50 AM   #121
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Originally Posted by vader100 View Post
Not sure how you can have NOTHING as an answer, are you supposed to only see one set of numbers with each eye? Maybe I am misunderstanding what you are supposed to see with each eye closed. The way I read it is that with my right eye closed I can see almost all of both sets of numbers which is absolutely awful, almost maximum amounts of crosstalk?

Can someone enlighten me?
Exactly. It's a bit confusing can someone clarify ?
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Old 10-08-2012, 10:44 AM   #122
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Originally Posted by AlbaJoeReturns View Post
How is my score ? There wouldn't happen to be a table of models ?
No; you need to read through all 5 pages. That's not a great score but is similar to what other active users get. You're notice that Panasonic active models tend to get somewhat better results.

It would suggest your TV suffers from a lot of cross-talk although I'm guessing you'll say you don't notice it very much (that's what most owners say )

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Originally Posted by AlbaJoeReturns View Post
Exactly. It's a bit confusing can someone clarify ?
Many of the passive systems deliver a "NOTHING" result because crosstalk really is very low on these systems.

However, if you look at the figures closely then you'll notice the first digit is often "2", "3" or even "4". This would suggest the brightness is down a little and can explain why the 2nd panel really is blank (or NOTHING). To avoid 'cheating' I therefore recommend 'Auto' in picture settings is used to stop people pushing the brightness/contrast up or down (intentional or otherwise)

As a simple rule, the bigger the difference between the first number and the second number the better.
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Old 10-08-2012, 10:47 AM   #123
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Test that most of you seem to use is just bad.. It does not matter much if it "bottom half screen smaller visible number -> 4" or 10 or 20, what matter is what are worst situations and they are white object in black background or reverse.. that jumps to you eyes, not dark object over black background. Thats why I made that crosstalk checking video that has simple way to tell how much MAX (%) crosstalk is. It is not perfect at all for whole crosstalk story but it is good measurement of worst situation that is present in many movies.
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Old 11-08-2012, 11:55 PM   #124
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Originally Posted by Jason Shouler View Post
No; you need to read through all 5 pages. That's not a great score but is similar to what other active users get. You're notice that Panasonic active models tend to get somewhat better results.

It would suggest your TV suffers from a lot of cross-talk although I'm guessing you'll say you don't notice it very much (that's what most owners say )

Many of the passive systems deliver a "NOTHING" result because crosstalk really is very low on these systems.

However, if you look at the figures closely then you'll notice the first digit is often "2", "3" or even "4". This would suggest the brightness is down a little and can explain why the 2nd panel really is blank (or NOTHING). To avoid 'cheating' I therefore recommend 'Auto' in picture settings is used to stop people pushing the brightness/contrast up or down (intentional or otherwise)

As a simple rule, the bigger the difference between the first number and the second number the better.
Was a while since I did it but as memory serves me correctly when I was checking the numbers at top they were white but the ones below where black or certainly not filled white if you know what I mean. Is that normal ?
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Old 11-08-2012, 11:56 PM   #125
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Originally Posted by Finjogi View Post
Test that most of you seem to use is just bad.. It does not matter much if it "bottom half screen smaller visible number -> 4" or 10 or 20, what matter is what are worst situations and they are white object in black background or reverse.. that jumps to you eyes, not dark object over black background. Thats why I made that crosstalk checking video that has simple way to tell how much MAX (%) crosstalk is. It is not perfect at all for whole crosstalk story but it is good measurement of worst situation that is present in many movies.
will give this a go but is there a reference which tells me Good, OK, Bad ?
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Old 12-08-2012, 7:13 PM   #126
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Originally Posted by AlbaJoeReturns View Post
will give this a go but is there a reference which tells me Good, OK, Bad ?
Well, Good is 0-5% but that might be possible with passive 3d, active LCD classes give anywhere between 10-30%... If I remember right 63C7705 was about 25% and my current 64E8005 is about 17%... looks bad by numbers but other than black-white extremes 64E8005 performs very good (black on grey background is close to 0% crosstalk..)

If I get time I'll try to do test video that shows more than extreme crosstalk numbers..
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Old 12-08-2012, 7:15 PM   #127
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Originally Posted by AlbaJoeReturns View Post
Was a while since I did it but as memory serves me correctly when I was checking the numbers at top they were white but the ones below where black or certainly not filled white if you know what I mean. Is that normal ?
You're the only one who can really say what it looks like on your set.

With both eyes open you should be able to see both sets of numbers (top and bottom).

When you close one eye then one set of numbers should disappear completely (this would assumes your TV has no cross-talk) Being able to see numbers in both the top and bottom panels (remember with one eye kept closed) indicates how much cross-talk you can see. You should read off the darkest number you can still just read from both panels.

You should now do the same but with your other eye closed. In theory the result should be exactly the same but with numbers reversed.
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Old 13-08-2012, 12:55 AM   #128
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Wow my LG tv seems to have a really big issue with ghosting from the first test on here. I can see both sets of numbers nearly throughout the test. When watching 3D content I have noticed some ghosting especially at the bottom right of the screen and close images look really blurry. The few reviews I found before buying the tv seemed to give it good revies and mentioned no problems with ghosting. Slight concern now it's an issue with the set itself!?

Not sure how good this will look here but I just took a photo through each eye of the glasses, right first then left. Looks similar to what I see with my own eyes!


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Old 13-08-2012, 10:44 AM   #129
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Originally Posted by iCaptnSpaulding View Post
I can see both sets of numbers nearly throughout the test.
You're supposed to try to read the darkest numbers you can so your image would suggest (assuming your camera sees the same as YOU which is unlikely)

4 - 29

That's actually a reasonable score overall but agree it's bad for a passive set.

Have you:
  1. Made sure you're using quality passive glasses (see post #79)
  2. Made sure your vertical viewing angle is directly aligned with middle of screen (see post #99)

Last edited by Jason Shouler; 13-08-2012 at 10:49 AM.
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Old 13-08-2012, 1:48 PM   #130
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I'm using the LG glasses that came with the TV so would have thought they were decent quality.

I think it could be from where I'm sat maybe as we have a small room, it's a 42" TV and on a tv cabinet around 50cm tall and maximum 6ft from the sofa. If I sit on the floor just at the bottom of the sofa then the picture is blurrier again so maybe I need to be back further?
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Old 13-08-2012, 2:54 PM   #131
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Quote:
Originally Posted by iCaptnSpaulding View Post
...it's a 42" TV and on a tv cabinet around 50cm
I'd expect a 50cm TV stand to be about spot-on but you might want to check the TV really is vertical (not leaning forwards or backwards).

If that doesn't provide the answer then I'd definitely try different glasses - just to make sure
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Old 13-08-2012, 7:50 PM   #132
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Originally Posted by Jason Shouler View Post
I'd expect a 50cm TV stand to be about spot-on but you might want to check the TV really is vertical (not leaning forwards or backwards).

If that doesn't provide the answer then I'd definitely try different glasses - just to make sure
Any recommendations on good quality passive glasses? Are there different types I need to look out for to make sure it's compatible? Thanks
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Old 14-08-2012, 10:07 AM   #133
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Originally Posted by iCaptnSpaulding View Post
Any recommendations on good quality passive glasses? Are there different types I need to look out for to make sure it's compatible? Thanks
You'll find loads on eBay/Amazon and you should look for "circular polarised"

I've only ever bought two:

£1.50 pair - work 100% but not very stylish
£5.50 pair - really comfy to wear but with 'defective' lens.
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Old 14-08-2012, 8:31 PM   #134
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OK did it again:


Left eye open/right closed -> top half screen smaller visible number -> 2
Left eye open/right closed -> bottom half screen smaller visible number -> 10
Right eye open/left closed -> top half screen smaller visible number -> 10
Right eye open/left closed -> bottom half screen smaller visible number -> 2

I have based this on what is easily recognisable as opposed to knowing what the number is based on its sequence.
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Old 14-08-2012, 8:41 PM   #135
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Originally Posted by Finjogi View Post
Well, Good is 0-5% but that might be possible with passive 3d, active LCD classes give anywhere between 10-30%... If I remember right 63C7705 was about 25% and my current 64E8005 is about 17%... looks bad by numbers but other than black-white extremes 64E8005 performs very good (black on grey background is close to 0% crosstalk..)

If I get time I'll try to do test video that shows more than extreme crosstalk numbers..


3D Screen Quality Test vid. Top-Bottom format 1080p
3D Screen Quality Test vid. Top-Bottom format 1080p

Thumbs up if useful so other people can find it.

Part 1: Alias and resolution testing - A flat image, with various test patterns.
This video is separated in a top down manner. Left channel top, right channel bottom. The top-bottom format is ideal for screens with alternating rows of parallax barriers, such as most passive consumer 3D TVs.
On Passive FPR 3D TVs, this test video will be equivalent to full 3d, since every other row of pixels alternates polarity.

Part 2: Cross talk testing - The entire color gamut on each channel, contrasted with a solid white, 50% grey, and black on the opposite channel.
First, close the right eye to see crosstalk from the right channel. And then close the left eye to see crosstalk through the left.
This is arguably the most important test of all. Ideally, the left eye never sees any of the image meant for the right eye, and vice versa. 3D depends on the left and right eye seeing completely different images. The more cross talk, the more impeded the 3D effect.
Although it's typical to see some crosstalk, brighter than 80% (see lower right quadrant) is fail. Always pick the screen/projector/glasses with less crosstalk. If you're using red/cyan glass for 3D, you can also use this part of the video to compare glasses.

Part 3: Sync Testing - Flat vertical motion at varying speeds.
This part tests for time sync between the left eye and right eye, which can be a problem for any 3D technology that continually switches between a left image and right image, such as displays with active (battery powered) shutter glasses.
Off sync left/right channels may appear as stuttering or unexpected depth.

Part 4: Parallax and depth testing - Points that test 3D comfort.
The recommended viewing distance for 3D videos is as close as 1.5 the width of your display. And as far as 3 times the width of your display.
The absolute maximum recommended parallax for 3D Videos is 5%
A maximum comfortable amount of 3D is around 1.5% to 2%
A suggested typical amount of 3D is around 0% to 1.5%
A noticeable amount of 3D is one tenth of a percent
The 10% portions are for testing only. Never use that amount in real life. It will result in puke.

I am a bit of a simpleton so can you please elaborate on the above ?

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Old 14-08-2012, 9:45 PM   #136
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LEFT

RIGHT


ANOTHER LEFT


ANOTHER RIGHT
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Old 15-08-2012, 10:35 AM   #137
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Arrow Explanation!

If anyone is confused

AbleJoe is talking about the tests I mentioned in post #111 (which have nothing to do with Finjogi)

Although interesting I didn't find them that useful.
  1. The hi-res passive test seems to be wrongly encoded as it doesn't match the sharpness of the one I produced in another thread.
  2. The cross-talk tests are very difficult to graduate (I can read effectively none on my set)
  3. Can't make much sense of the last two tests


@AbleJoe, are you just showing off your back-light

Last edited by Jason Shouler; 15-08-2012 at 1:38 PM. Reason: light-light ??
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Old 15-08-2012, 1:26 PM   #138
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There is nothing Able about this Joe me lol

Yeah I just assumed it might be the same stuff tbh .... I knew I had downloaded a different test a while back. So there must be 3 different tests on the go then ?

I also cannot understand what I am looking at tbh

You likey shiny things? I doooooooo myyyyyy preciousssssssss
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